A color printer may include a number of print heads. A print head may, for example, contain dies, wherein each die may be associated with the same or different colors. A die may provide lines or rows of fluid ejection nozzles, also referred to as nozzle trenches. When printing with a number of print heads, using a multi-pass printing mode, masks may be applied to the nozzles to selectively deposit droplets of printing fluid on a print medium, pass by pass, to control the printing process. Print masks may help to prevent or reduce visible artifacts, such as image banding.